# hyhetra
hyhetra (HY-HE-TRA) is a package for hydraulics and heat transfer calculations.
# Objectives
The package was initially developed to study district heating and cooling systems, but its scope has been and will hopefully continue to be broadened. The aim is to have a library that can be relied upon for studying hydraulics and heat transfer topics. The focus is not on finite-element approaches but rather on steady-state, one- or two-dimensional models that can be easily understood, validated and used.
# Status
The package is not regarded as finished nor bug-free.
# References
This package contains selected formulas compiled in the following publications:

* Y. Cengel, Heat Transfer: A Practical Approach, 2003

* F. Incropera et al., Fundamentals of Heat and Mass Transfer (6th edition), 2006

Some original sources were also consulted, namely:

* Benny Bøhm, On transient heat losses from buried district heating pipes, Int. J. Energy Res. 2000; 24:1311-1334 https://doi.org/10.1002/1099-114X(200012)24:15%3C1311::AID-ER648%3E3.0.CO;2-Q

* P. Wallentén, Steady-state heat loss from insulated pipes, Byggnadsfysik LTH, Lunds Tekniska Högskola, 1991 https://portal.research.lu.se/en/publications/steady-state-heat-loss-from-insulated-pipes

* S. Frederiksen and S. Werner, District Heating and Cooling, 2013 Studentlitteratur AB, ISBN-10 9144085303, ISBN-13 978-9144085302 https://www.studentlitteratur.se/kurslitteratur/teknik-datorer-it-och-bygg/energiteknik/district-heating-and-cooling/

# Dependencies
numpy, scipy
# License
This package is released under version 3 of the GNU General Public License.
# Disclaimer
This package is provided without warranty of any kind and its developers assume no responsibility for its use.
# Data
The package is best used by loading data about fluid properties, such as water, and geometries, such as pipes. CSV files can be used for this purpose in accordance with predetermined formats. The packages hyhetra-fluiddata and hyhetra-pipedata (available separately) include sample files for common fluids and pipes to get you started.
# Contributions
Contributions to this package are welcome. The usual protocols and rules apply.
# Acknowledgements
The development of this package initially benefitted from the support of ERA-Net Smart Energy Systems and Innovation Fond Denmark through the TOP-UP project (project references 91176 and 9045-00017A, respectively).

The original release can be found in: https://lab.compute.dtu.dk/pmag/topupheat
